All the 3rd child want to make pbar visible=>false. I tried and i can change the value of all 3rd childs to 22 and it works, but visible=>false doesn't change the state of visibility and i dont understand why because is a attribute og Gtk2::CellRenderer and it should works, but it doesn't.

but with the 3th child how can i set the property of progressbar at visible = false, this will affect to the other parents using same model, isn't it?

You must set up some way to discern that from the model. The column will inspect its attributes list or cell data func for every row, to set up each cell for this row and draw. I can't really experiment to show you an example (i'm on vacation, away from a machine on which to hack), but here is some pseudocode:

# another column in the model, COL_PBAR_VISIBLE, tells us whether
# we need to use the progressbar. Map this directly to the "visible"
# property on the renderer.
$column->add_attributes ($progress_renderer,
value => COL_PBAR_VALUE,
visible => COL_PBAR_VISIBLE);

Or, next possibility:

# if we have to use some complicated condition to calculate whether
# to use the progressbar, the cell data func is more appropriate.
$column->set_cell_data_func ($progress_renderer,
sub {
my ($column, $cell, $model, $iter) = @_;
my $value = calculate_progress ($model, $iter);
if (defined $value) {
# we should show the progress bar
$cell->set (visible => TRUE, value => $value);
} else {
# we should NOT show the progress bar, so don't
$cell->set (visible => FALSE);
}
});

Remember that cell data functions are called rather often, so you don't want to do something expensive there.

The principle is that the attributes on each cell in the column are somewhat distinct. You might have to add_attributes() for the text renderer after setting the data func, the docs are not entirely clear and i can't experiment at the moment.

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